0:07Skip to 0 minutes and 7 secondsSo we use the term "dementia" but I understand that is a term that covers a lot of different diseases and conditions. Could you tell us a little bit more about that? Yes, that's right. "Dementia" is an umbrella term. It's what we call a clinical syndrome. It's the memory loss symptoms and a lot of other symptoms that occur and can be due to lots of different diseases. The most famous, of course, is Alzheimer's disease. That causes more than half the cases of dementia. So more than half the people have Alzheimer's disease, particularly older people. But the other major causes are Lewy body dementia, vascular dementia, and in younger adults, frontal dementia.

0:47Skip to 0 minutes and 47 secondsAnd they and those between them make up the vast majority of cases and then there's a lot of other rarer diseases that cause dementia, as well. So can you tell us some of the typical symptoms of dementia? The hallmark symptom that I think everybody is aware of now is the memory loss and that's most characteristic then of Alzheimer's disease. And so with people with Alzheimer's disease, we get a very typical pattern of onset, particularly in older people, where memory is the prominent symptom and the one that brings them to the doctor in the first place.

1:25Skip to 1 minute and 25 secondsWith other causes of dementia, such as vascular dementia and Lewy body dementia, then other symptoms can be the most problematic symptoms early on and the ones that cause them to see the doctor. So it's not just memory symptoms. It's other things. So for example, I will usually be referred somebody with dementia who has "memory loss" written in the letter from their general practitioner. But often, I will be sent a letter from somebody who is said to have depression or depressive symptoms and that is the concern that the family or the patient has. And in fact, a lot of those people don't have the clinical syndrome of depression, a depressive illness.

2:12Skip to 2 minutes and 12 secondsThey have dementia and the depressive symptoms are an early feature of that. And it's probably depression as well as memory that's the most common way in which people would come to see a specialist like myself. And are there any treatments? Treatments for the symptoms? Yes. So yes, we distinguish between treating the symptoms and treatments of the diseases themselves. So there's a syndrome of dementia that's different diseases and so there is symptomatic treatments like for depression, where we could use either a psychological approach to managing the depressive symptoms or drug treatments, antidepressants for those depressive symptoms. If somebody has other problems, like difficulty sleeping, again, we would look to have a non-pharmacological approach to help people to sleep.

3:06Skip to 3 minutes and 6 secondsBut if that doesn't work well, then we would, again, look to use drugs to help people sleep, so-called "sleeping tablets." So we have symptoms that we recognise and target with specific drugs or non-pharmacological approaches. In terms of diseases then, there are treatments being developed but at the moment, unfortunately, there aren't any what we call "disease-modifying treatments," that is, a treatment for Alzheimer's disease that will stop the disease itself or even reverse the disease process in the brain. There are a lot of drug trials going on trying different new treatments but at the moment, there's nothing available for people to help with the disease itself, Alzheimer's or sadly, any of the other major diseases, either.

Types and symptoms of dementia

In this video, Professor Alan Thomas describes the different types of dementia and the most common symptoms.

Dementia is an umbrella term describing diseases of the brain that lead to symptoms such as reduced memory, language and communication ability, and difficulty processing information to make decisions. A person may be affected by one or more of these. Here are some of the more common types:

Alzheimer’s disease (AD)

Alzheimer’s is the most common type of dementia, mostly affecting older people. The disease develops as protein deposits in the brain (known as plaques and tangles). People with Alzheimer’s disease struggle with memory, difficulty with new learning and recall. Over a number of years, the disease affects more areas of the brain. As the disease progresses, a person may also develop confusion, and have difficulties communicating because of difficulties with speech production.

Dementia with Lewy bodies (DLB)

Lewy bodies are proteins that develop in the cortex. A person with dementia with Lewy bodies (DLB) can develop similar symptoms to Parkinson’s disease (tremor, muscle rigidity, shuffling gait, lack of facial expression, monotonous voice) as well as cognitive symptoms such as visual hallucinations and fluctuating cognition.

Vascular dementia (VD)

Problems with blood vessels are associated with vascular dementia. Reduced blood flow to the brain damages brain cells, and results in difficulties with what is called ‘executive function’, such as planning and organising skills.

Frontotemporal dementia (FTD)

This type of dementia is often developed at a younger age than other types of dementia, and survival periods are usually shorter. People living with this type of condition may experience difficulties with their speech, and major changes in personality and the ability to moderate their behaviour.